World Partition says 0.00km in Size

Development World Creation
,
1
  1. Open New Level, select “Empty Open World”
  2. Add a landscape and actors
  3. “World Partition” panel shows no cells and a size of 0.00kmx0.00kmx0.00km

The size should obviously be bigger then zero. How do I update the World Partition dimensions? Shouldn’t it update automatically?

Cheers!